You feel most powerful when…

… you are acting from a place of self-motivation and self-drive, you feel capable and competent in your work and you are connected to others, to the goal, and to the social frame within which you are acting.

So says the self-determination theory of motivation, proposed by Deci and Ryan, which considers the intrinsic motives (your internal world) and the extrinsic forces (e.g., the environment, other people), coupled with social and cultural elements in determining how we behave in effective and healthy ways.